Review Flashcards
What is an aliphatic molecule
Greasy feel, hydrocarbon chain. No s+ or s-
Aromatic?
Has a smell. Electrons move around in a circle. Needs a ring
What are the three rules for identifying an aromatic compound?
1) huckels rule
2) every atom contributes
3) planar molecule
How to identify an aromatic compound
1) huckels rule 4n+2 = 2, 6, 10, 14, 18
2) no sp3 must be planar
3) conjugated and planar
8-12 in huckels rule means rings buckle and molecule is not planar
How to identify an anti-aromatic compound?
1) conjugated
2) planar
3) huckels rule 4n=4, 8, 12, 16
When is a compound non-aromatic?
When any conditions are not met
Nucleophile?
Positive seeking. Negative charge
Electrophile?
Negative seeking. Positive charge
Heteroatoms?
N, S, O any atom that is not a carbon or hydrogen
F-C alkylation?
Adds an alkyl halide with a Lewis acid catalyst
F-C acylation?
An EAS reaction. Benzene reacted with acyl chlorides or hydrides with a Lewis acid catalyst
EAS reaction
An atom is replaced with an electrophile
Activating groups?
Otho, para directors. Electron donating groups. Increases EAS rate of reaction
Ortho?
Carbon next to activating group.
Para?
Carbon directly across from activating group. 3 carbons away
Using ortho and para which one is thermodynamic and kinetic?
Otho is kinetic
Para is thermodynamic
Strongly activating groups?
NH2, NHR, OH, OR
Moderately activating groups?
NHC=OR, OC=OR
Weakly activating groups?
-R, Aromatic ring, CH=CH
Deactivating groups?
Meta directors, decreased rate of EAS. Electron withdrawing.
Meta?
Two carbons away from deactivating group.
Weakly deactivating?
DOP
F, CL, Br, I
Ortho, para directors.
Moderately deactivating?
C=O-H, C=O-CH3, C=OCH3, C=O-OH
Strongly deactivating?
NO2, CN, NR3, SO3H
If a molecule has multiple groups which one do you follow?
Strongly activating ——> strongly deactivating
Thermodynamics?
Hot and slow reactions. Makes a more stable product.
Kinetic?
Cold and fast reactions. Makes the easiest product
When will a friedel crafts reaction not occur?
When there is monosub deactivating group. Electron withdrawing.
Also if there is an NH2 group as it will interfere with AlCl3
What atom do you look at when deciding activating or deactivating?
Benzylic carbon ( one carbon away from pi bond)
Diazonium salt?
Anything with a N2. It is the best leaving group.
Conjugation.
Single bond, pi bond, single bond, pi bond…
If extended it is a colour (light is absorbed)
How many NO2 groups makes an molecule explosive?
3 or more
PKa
Ph=PKa
-logPKa = Ka
LogKa = -PKa
Ka = 10^-PKa
Lewis base?
Has unpaired electrons more basic
DBE
DBE = C - (H/2) + (N/2) + 1
Fehlings Test
Aldehyde give red precipitate.
Tollens Test
Looks like a mirror. Ag(NH4)OH-
Haloform test
Acetyl group CHI3 makes really yellow
